1. Field of the Invention
The present invention relates generally to an apparatus and a method for fluid-treating photographic film having a disc shaped configuration. More particularly, the invention relates to an apparatus and a method in which a film disc is rotated in a processing solution to transform a latent image on the disc into a visible one.
2. Description of the Prior Art
A variety of devices are known for processing photographic film. Common concerns for processing film in these devices are the desire to minimize or eliminate mechanical contact with the front and back surfaces of the film and the desire to obtain an intimate contact between the film surfaces to be processed and the processing solutions, without any external contaminates or any carryover between different processing solutions. Further desires, from the economic viewpoint, are to provide processing apparatus which is low in cost and simple in operation and to minimize the quantities of processing solution used.
The majority of known processing apparatus has been designed for use with strip film. Two well known general types of processors for strip film are (a) reel processors in which film strips are spirally wound about a reel that is rotated in a processing solution and (b) continuous processors in which film strips spliced end-to-end are fed over a vertically disposed roller rack assembly, first down one side of a tank of processing solution and then up the other side of the tank.
Processors for discrete film units, especially in a disc shaped configuration, are less known, although versions of film discs and cameras that used the discs were first developed some time ago. The scarcity in the prior art of processing apparatus for film discs may indicate that earlier versions of the film discs were, for the most part, processed individually by hand.
More recently, discrete film units having a disc shaped configuration have been developed for use in a modern camera. The film disc and the camera, as well as a cartridge for the film disc, are disclosed in commonly assigned, copending U.S. Pat. Application Ser. No. 931,053, filed Aug. 4, 1978. The film disc has a central aperture about which is concentrically disposed a plastic hub member. The hub member is permanently attached to the disc of photographic film and includes a keyway by which the hub can be secured to a keyed spindle for rotation of the film disc during processing. An example of a processor for the film disc is disclosed in commonly assigned U.S. Pat. No. 4,112,454 patented Sept. 5, 1978. The disclosed processor includes a spindle on which a plurality of film discs may be secured in substantially parallel, hub-to-hub relation. The spindle and the film discs are first rotated in a tank of developing solution and then are withdrawn from the tank and rotated to discharge, by centrifugal force, excess solution that may tend to cling to the spindle and the film discs. Following this, the spindle and the film discs are placed in another tank of processing solution, such as fix or wash, and the steps of spinning the discs in the solution and out of the solution are repeated. After processing in all of the required solutions has been completed, the film discs are spun until dry.
Other examples of film disc processors are disclosed in commonly assigned U.S. Pat. Nos. 4,112,452 and 4,112,453, both patented Sept. 5, 1978 and commonly assigned U.S. Pat. Applications Ser. No. 883,756 and 906,169, filed Mar. 6, 1978 and May 3, 1978 respectively.